Definition: You are given a question on jurisprudence. Jurisprudence is the theory or philosophy of law. You are also given 4 answer options (associated with "A", "B", "C", "D"), out of which only one is correct. You need to answer the question by selecting the correct option. You should only answer with the choice letter, not the whole answer.
Input: The following person is the author of the book ‘The Concept of Law’ :
(A)Hart (B)Austin (C)Bentham (D)None of the above

A